Electric-brush holder



No. 752,376. 7 PATENTED FEB. 16, 1904. DE WITT G. GOOKINGHAM.

ELECTRIC BRUSH HOLDER.

APPLICATION FILED 001. 15. 1903.

no MODEL.

m Wm

UNITED STATES Patented February 16, 1904.

PATENT OFFICE.

DE WITT O. OOOKINGHAM, OF CLEVELAND, OHIO, ASSIGNOR OF ONE- HALF TO JOHN H. HERTNER, OF CLEVELAND, OHIO.

ELECTRIC-BRUSH HOLDER.

SPECIFICATION forming part of Letters Patent No. 752,376, dated February 16, 1904.

Application filed October 15, 1903. Serial No. 177,169. (No model.)

To all whom it may concern.-

Be it known that I, DE WITT O. OooKINe- HAM, a citizen of the United States, residing at Cleveland, in the county of Ouyahoga and State of Ohio, have invented a certain new and useful Improvement in Electric-Brush Holders, of which the following is afull, clear, and exact description, reference being had to the accompanying drawings.

The object of the invention is to provide a simple and eflicient device for holding an electric brush against the surface of=a movable commutator.

The invention may be here summarized as the construction and combination of parts shown in the drawings and hereinafter described, all as pointed out definitely in the claims.

In the drawings, Figure 1 is a side elevation, Fig 2 a top plan view, and Fig. 3 is a bottom view, of the invention. Fig. i is a perspective view of the member D, and Figs. 5 and 6 are views showing modified forms of the upper end of the brush and of the part of the pressure-arm which engages therewith.

Referring by letters to the parts shown in the drawings, A represents the commutator, and B afixed stud or rod to which the brushholder is adjustably fixed.

The contact device includes abrush O, which is preferably made of carbon, and a brushholder, which includes the fixed member D and the movable spring-actuated pressure-arm E. The member D has a split sleeve (Z, which embraces the rod B and is adjustably clamped thereon. It may be, however, connected with this rod or with any other support in any suitable manner. The member D has also a finger d, with a broad rounded end, which occupies a position as close as practicable to the surface of the commutator. The arm E- is pivoted to the member D. In the preferred construction this pivotal connection is affected by means of a stud 6Z2, which is integral with the member D, and a sleeve 0, which is 'a part of the arm E, which embraces this stud, said arm lying upon the thin upper end of the member D. The brush O has its lower end inclined on an are which fits the surface of the commutator. The front face of the brush bears against the finger d, and the outer end of the arm E bears down upon the upper end of the brush and holds it always in contact with the commutator. The upper end of the brush and the under surface of the upper end of the arm E have, respectively, a projection and a recess which receives it.

In the preferred construction there is an angular recess 0 in the under side of the arm E, and the brush has an angular projection c at its upper end, which enters this recess. The inclination of the engaging surface of the brush and commutator, together with the downward pressure upon the brush from this arm E, causes the brush to press against the finger d. This action, coupled with the fact that the upper end of the brush is prevented from turning on said finger d as a fulcrum by the engagement of the projection c in the recess 6 holds the brush in substantially one position relative to the commutator. Of course as the lower end of the brush wears away and the arm E swings on its pivot to press the brush downward the upper end of the brush will swing a little on the finger (Z. The described construction permits this much movement of the upper end of the brush, but prevents any greater movement thereof. Having in mind the purpose for which the brush and arm are provided with the recess and projection referred to, it is apparent that considerable latitude is permissible in their construction and arrangement. For example, the recess may be in the brush and the projection on the arm, as shown in Fig. 5, or the recess and projection instead of being angular may be in the form of a circular are, as shown in Fig. 6, or they may have other forms which need not be enumerated.

In Fig. 1 is shown another characteristic of construction which goes to the betterment of the device, although not absolutely essential to its successful operation. In the construction referred to the upper end of the brush has fitted to it'a metallic cap G, with which the arm E engages. This construction decreases the resistance which the current encounters in passing from the brush to the arm.

A part of the current also passes from the brush to the finger (Z. Because of the shape of this finger it is not likely that the brush would ever become stuck to it, as sometimes happens when the brush has a broad flat surface in sliding contact with a broad metallic surface forming a part of the brush-holder, and it is not likely that the electrical contact between the finger and brush will be impaired.

Another characteristic of the construction shown, which likewise goes to the betterment of the device, but is not essential to the generic invention, is the fact that the brush-holder is composed of two easily-separated parts namely, the member D and the arm E, with the attached spring. The construction shown is also exceedingly cheap and thoroughly effective for the intended purpose.

On the member D is a flange (P, which extends behind the main part of, said member. A finger e, projecting from the arm E, passes under the extended part of this flange when the device is in use, and thus prevents the accidental disengagement of arm E from member D. If the brush is removed, however, and the front end of the arm moved down, this finger passes from beneath the flange, and the arm E may then be removed.

The operating-spring K surrounds the sleeve 6 and is attached at one end to the arm E. The other end of said spring may be inserted in either of several notches in the flange d", and thereby the spring may be put under the desired tension.

Having described my invention, I claim 1. The combination, with a commutator, of a brush-holder provided with means for exerting a pressure on the upper end of the brush upon substantially the longitudinal axis thereof, and means for engaging said brush laterally at substantially a single point in the length thereof for resisting the thrust caused by the movement of said commutator.

2. The combination, with a commutator, of a brush-holder, an arm carried by said holder for engaging the brush and exerting a pressure upon the same in the direction of its longitudinal axis, and means engaging said brush laterally at substantially a single point for resisting the thrust caused by the movement of the commutator, and means for exerting a pressure upon said arm.

3. The combination, with a commutator, of a brush-holder, an arm carried by said holder for engaging the brush and exerting a pressure upon the same along its medial plane, and means engaging said brush laterally at substantially a single point for resisting the thrust caused by the movement of the commutator, and a spring for exerting a pressure upon said arm.

4:. The combination, with a commutator, of a brush-holder, means in connection with said holder for exerting a pressure on the upper end of the brush upon substantially its longitudinal axis, and a rigid arm engaging said brush laterally at substantially a single point and thereby resisting the thrust caused by the movement of the commutator.

5. The combination, with a commutator, of a brush-holder, means in connection with said holder for exerting a pressure on the upper end of the brush upon substantially its longitudinal axis, and a rigid arm tapering toward said brush and engaging the same laterally at substantially a single point and thereby resisting the thrust caused by the movement of the commutator.

6. The combination with a commutator, and an electric brush, of a fixed brush-holder member having a finger for engaging the front side of said brush, and a spring-actuated pressure member engaging with the top of the brush, said brush and pressure member having, respectively, at their point of engagement, a projection and a recess which receives the same.

7. The combination with a commutator, and an electric brush, of a fixed brush-holder member having a finger for engaging the front side of said brush, and a spring-actuated arm pivoted to said member and engaging with the upper end of the brush, said brush and arm having, respectively, at their point of engagement, a recess and a projection which enters the same.

8. The combination of a commutator, and a carbon-brush, said brush having upon its opposite end an angular metal cap, with a brush holder having a fixed member which is pro vided with a finger against which the front surface of the brush engages, a spring-actuated arm pivoted to said member and having in the under side of its front end an angular recess which receives the angular cap on the brush.

9. In an electric-brush holder, the combination of a fixed member with which the brush engages, which member has an overhanging flange, with aspring-arm pivoted to said member and having a rearwardly-extended finger which swings beneath said flange.

10. In an electric-brush holder, the combination of a fixed member with which the electric brush is adapted to contact, with a pressurearm removably pivoted to said member, a spring secured to said arm and'engaging with said fixed member to put the spring under the required tension.

11. In an electric-brush holder, the combination of a fixed member having a finger for contact with the electric brush and having a pivotstud, an arm having a sleeve which embraces said pivot-stud, thereby pivoting the arm to said member, a spring coiled about said sleeve and secured to the arm, their being an adjustable connection between the other end of said spring and the fixed member.

12. In an electric brush, the combination of a fixed member having a finger for contact with the electric brush, and having an overhanging IIO flange Whose upper end is notched, a pressure- In testimony whereofIherennto aflix my sigarm pivoted to said member, asprlng secured nature 1n the presence of two Witnesses.

to said arm and adapted to engage in any of r w the notches referred t0 to vary the tension of DE VVITT COOKINGHAM' 5 the spring, said arm also having a rearwardly- WVitnesses:

extended finger Which passes beneath the over- N. L. BRESNAU, hanging part of said flange. B. WV. BROOKETT. 

